Question

which of the following formulas is correct?

a

d

b

c

Explanation:

• For \(Mg^{2 +}\): Magnesium (\(Mg\)) is in Group 2 of the periodic table. Elements in Group 2 tend to lose 2 electrons to form cations with a \(+ 2\) charge. So, \(Mg^{2+}\) is a correct ion formula.
• For \(B^{3-}\): Boron (\(B\)) is a metalloid. It is more likely to form covalent compounds rather than simple \(B^{3 -}\) anions. In ionic compounds, it usually forms more complex ions.
• For \(Li^{1-}\): Lithium (\(Li\)) is in Group 1 of the periodic table. Elements in Group 1 tend to lose 1 electron to form cations (\(Li^{+}\)), not anions (\(Li^{-}\)).
• For \(I^{1 +}\): Iodine (\(I\)) is in Group 17 of the periodic table. Elements in Group 17 tend to gain 1 electron to form anions (\(I^{-}\)), not cations (\(I^{+}\)).

Answer:

A. \(Mg^{2+}\)